The ultimate objective of the proposed pilot study is to elucidate fundamental aspects of the genetic architecture of the baboon craniofacial complex in order to develop an appropriate animal model for study of the genetic contributions to normal variation in the human craniofacial complex. Understanding the nature of genetic influences on the regions of the cranium is of primary concern to a wide variety of clinicians. As it becomes increasingly possible to incorporate gene therapy and tissue engineering when approaching repair of craniofacial dysmorphology, studies that elucidate the genetic underpinnings of continuous phenotypes typifying normal variation in craniofacial morphology are of critical importance. The significance of this research will be the elucidation of the genetic architecture of the craniofacial complex in a species in phylogenetic proximity to humans. Examination of genetic contributions to normal variation in the baboon craniofacial complex will be addressed in two specific aims: 1) Collect quantitative measures of craniofacial morphology in baboons in order to characterize variation in biomedically-relevant phenotypes. 2) Explore fundamental aspects of the genetic architecture of craniofacial morphology in baboons. Fourteen craniometric points will be marked on lateral cephalographs of a sample of 400 baboons from the Southwest National Primate Research Center. Twenty linear and 5 angular metrics will be taken for each animal based on the craniometric points. A maximum likelihood variance decomposition method for pedigree data using the algorithm implemented in the software program SOLAR is the analytic platform for the analyses. Heritability of each trait will be estimated, and genetic and environmental correlations matrices will be examined for all traits. Additionally, preliminary linkage analysis will begin to look for Quantitative Trait Loci (QTL) harboring genes influencing variation in adult craniofacial morphology in baboons. This study of the genetic architecture of the craniofacial complex in baboons will provide the necessary ground work needed to establish the baboon as an animal model for the study of genetic and non-genetic influences on craniofacial variation. [unreadable] [unreadable]